Molecular testing focuses on detecting specific DNA or RNA sequences associated with particular health conditions. When properly performed, molecular assays are highly accurate. In some cases, molecular testing can confirm a preliminary clinical diagnosis.

Several techniques can detect the presence of target genetic material within a cell, each operating through slightly different principles. Examples of techniques used in a molecular laboratory include:

• Fluorescence in situ hybridization (FISH)

• Chromosomal microarray analysis

• Karyotype (Cytogenetic analysis)

For each technique, clinicians collect a biological sample from the patient, which is then processed using specific laboratory methods to make the genetic material more visible or analyzable. A laboratory technologist examines the prepared sample under a microscope or through specialized analytical systems and provides a diagnostic report.

Molecular testing is a form of genetic testing that offers significant insight into an individual’s genome. It can also detect signs of infections and certain diseases based on the unique genetic characteristics of those conditions. This field is rapidly evolving, with expanding testing options becoming increasingly available.

Genetic sequencing technologies, particularly next-generation sequencing (NGS), continue to improve in accuracy, speed, and scope. However, it is important for individuals to understand the limitations of molecular testing. This is especially relevant for certain genetic tests—such as prenatal screening—where results may not always provide absolute certainty.